Tafsir of An-Nazi'at 79:21

He denied Moses, peace be upon him, and labeled his miracle as sorcery, and he disobeyed God Almighty by rebelling after having known the truth of the matter and the obligation of obedience. This is the most severe and ugliest form of disobedience, as he dared to deny the very existence of the Lord of the Worlds from the outset.

The accursed one and his people were commanded to worship Him, the Almighty and Majestic, and to abandon the greatness that the tyrant claimed for himself—which his rebellious faction would attribute to him—not merely commanded to release the Children of Israel from captivity and coercion.

In making the object of the denial "Moses, peace be upon him," and the object of the disobedience "God, the Almighty and Majestic," there is an intensity of censure that is absent if both were attributed to Moses—as it has been said—in the phrasing "he denied Moses and disobeyed him," as is not hidden.